Clipping masks vs. alpha lock in digital painting
Use a clipping mask when you want the shading on its own editable layer. Use alpha lock when you want to repaint the pixels that are already on the active layer. Both keep paint inside a shape. Try both on the same yellow lemon and the difference is easy to see.
Paint a base shape
In PaintLasso, choose New document, set Background to Transparent, and create a small square canvas. On the first layer, paint a solid yellow oval with an opaque brush. Leave blank space around it. Name the layer Lemon base so it stays easy to find.
Clip a shadow to the base
- In Layers, choose New layer and place it directly above Lemon base.
- Select the new layer and turn on Clipping mask in its layer controls.
- With a warm orange brush, drag a wide stroke across the lower-right side. Let the stroke extend past the edge of the oval. The portion outside the yellow shape stays hidden.
- Lower the shadow layer’s Opacity to soften the effect, or click its eye icon to hide it. The yellow base stays available as a flat color.
Shadow hidden
Clipped shadow visibleRecolor the base with alpha lock
Hide the clipped shadow and select Lemon base. Turn on Alpha lock in that layer’s controls. Brush lime green across the oval and beyond the edge. Green replaces yellow where there were already pixels, and the outline holds. Use Undo to restore the yellow if you want to compare both versions. The color change lives directly on the base layer.
When to use each control
Clip texture, light, or shadows when you expect to adjust their opacity or try a different color later. Use alpha lock for a quick recolor, such as changing a shirt from blue to green while keeping its silhouette. If a clipped stroke appears in the wrong shape, check the layer immediately below it. If alpha lock seems to do nothing, check that the selected layer already has paint where you’re brushing.
Related guides · Drawing with layers · Blend modes explained · Export transparent artwork